Breast cancer afflicts more than 140,000 women in the U.S. each year. Failure to deliver effective treatments compromises attaining cancer mortality reduction goals for the Year 2000. The proposed project seeks to increase the proportion of older women with newly diagnosed Stage I- III breast cancer who receive post-operative treatment (Tamoxifen and/or radiation). This will be done in two phases: first, we will examine the patient, family, physician and institutional factors that affect the likelihood that older breast cancer patients will receive post-surgical treatment; second, we will use this information to refine the implementation of two different interventions -- (1) hospital guidelines for breast cancer management and (2) surgical practice staff education and patient/family counseling. These interventions will be implemented within the context of a 2 x 2 randomized experimental design in which four participating hospitals are pair matched and randomly assigned to the guidelines intervention. Additionally, at least eight different practices affiliated with only one of the participating hospitals will be pair matched and randomly assigned to a special breast cancer treatment decision-making program intervention. Patients in experimental practices will receive one or more counseling sessions by a clinical specialist who will explain treatment options, clarify values and preferences, deal with concerns about toxicity and urge patients to choose a treatment consistent with NCI guidelines. The effectiveness of the two interventions will be assessed on the basis of the increase in the proportion of older women who receive minimal post-surgical treatment appropriate to their stage and type of surgery. A hierarchical analytic model will be used to incorporate physician practice and institutional effects and the assumed correlation among patients treated by the same physician. The process of implementing the interventions will be carefully documented in the experimental hospitals as well as in the office practices of volunteer surgeons.